Recapitulating Parkinson's disease pathology in a three-dimensional human neural cell culture model

Extensive loss of dopaminergic neurons and aggregation of the protein α-synuclein, into ubiquitin-positive Lewy bodies represents major neuropathological hallmarks of Parkinson's disease. At present, the generation of large nuclear associated Lewy bodies from endogenous wild-type α-synuclein, translationally regulated under its own promoter in human cell culture models requires costly and time-consuming protocols. Here, we demonstrate that fully differentiated human SH-SY5Y neuroblastoma cells grown in three-dimensional cell culture develop Lewy body pathology upon exposure to exogenous α-synuclein species. In contrast to most cell- and rodent-based models that exhibit multiple diffuse α-synuclein aggregates throughout the cytoplasm, a single large nuclear inclusion immuno-positive for α-synuclein and ubiquitin is rapidly obtained in our model without the need for over-expression of α-synuclein or genetic modification of the cell line. However, phosphorylation of α-synuclein within these inclusions was not observed. The system described here provides an ideal tool to screen compounds to therapeutically intervene in Lewy body formation and to investigate the mechanisms involved in disease progression in synucleinopathies.